Feminine pads, also referred to as sanitary napkins, such as those described in U.S. Pat. Nos. 4,397,644 and 4,079,739, are well known. Sanitary napkins of the prior art are normally of multilayered construction including: a fluid-absorbent core interposed within a fluid-impermeable baffle and a fluid-permeable cover. The cover being designed to transmit menstrual fluid or the like across its boundary to the absorbent core. As those skilled in the art will readily appreciate, the interrelationship of components is substantially more intricate; however, for purposes of basic understanding, the foregoing suffices. Within those very general parameters, one may also profitably compare the contoured sanitary napkin disclosed in U.S. Pat. No. 4,184,498.
Conventional sanitary napkins typically comprise an absorbing layer made of a hydrophilic absorbent material such as absorbent paper, absorbent cotton, pulverized pulp or the like, so that when having absorbed therein a large quantity of body fluid, the napkin becomes sticky on its surface. In addition, when the absorbing layer is subjected to pressure, the body fluid once absorbed therein is likely to ooze or flow out in a reverse direction toward the body of the wearer and can cause a sticky surface. Thus, the uppermost layer of the sanitary napkin becomes very uncomfortable to use and unsanitary. This problem is particularly apparent when body fluid is discharged in large quantities within a relatively short period of time in the initial stage of menstruation. Sometimes the absorbing layer is unable to fully absorb the discharge thereby permitting the body fluid to remain on the surface of the absorbing layer and allowing sideways leakage when the layer is subjected to varying body pressures.
Even at times of light flow, however, body fluids do not necessarily readily pass through the fluid-permeable cover into the fluid-absorbent core of the sanitary napkin. It has been recognized that menses is a complex fluid with uterine blood being only one component of its composition. Menses also contains cellular debris and a mucus-like fraction. The composition of menses has a significant effect on the transport of fluid from the cover into the absorbent matrix of a sanitary napkin, especially for certain women who consistently have high viscosity menses and comparatively low flow volumes. High viscosity menses tends to stay on the upper surface of the cover of the sanitary napkin.
The cover, or top layer of a sanitary napkin, is an important structural component respecting overall product efficacy, both objectively and subjectively from the user's point of view. A number of dichotomies become apparent when describing the ideal or preferred top layer of sanitary napkins. For consumer acceptance, a cloth-like texture and feel are preferred. In addition, the top layer should appear clean, dry and stain-free even during use. Thus, the cover layer should remain aesthetically pleasing even during use. Nonwoven webs which most economically and effectively achieve the objective of an acceptable cloth-like texture are, however, generally undesirable when evaluated on their ability to remain clean, dry and stain-free during use. With nonwoven webs, menses tends to get hung up or remain on the top layer while never reaching the lower absorbent layer since the fibers often act to block the path to the absorbent layer. Thus, the sanitary napkin becomes uncomfortable, wet, sticky and generally non-aesthetical.